Table ii



p 7 I a v Unlted States Patent "'ce 33135 Patented Jan. 31, 1956 H HiC-C=0 HC-C=O \O 2733235 0 om on, 3cn=on, H 4340 MINERAL OIL ADDITIVE 5 Hip-0:0 HC=CH(CHr)aCH Thomas Cross, Jr., Union, and Jeffrey H. Bartlett, West- For introducing the alkenyl groups desired in accordfield, J! assigllols E550 Research and Engineering ance with the present invention, any mono-olefin having p y, a cerpol'atlon of Delaware from 4 to 24 carbon atoms, preferably 6 to 16 carbon atoms, may be employed. Such olefins include normal N0 Drawmg s figf ggf g g g 1952 10 and branched chain olefins and polymers of the same, as well as mixtures of olefins occurring in technical products. 16 Clalms- Examples of suitable olefins include n-butylene, isobutylene, Z-ethyl-l-butene, diamylene, l-decene, l-tetradecene, l-octadecene, 6-24 polypropylenes, C16C18 olefins This invention relates to mineral oil compositions and f th Fischer synthesis, C24 dechlorinated wax, Particularly t0 lubricating Oils in Which an additive has cracked gasoline, and similar products. The preparation been incorporated to improve the Properties of the Sameof alkenyl succinic acids and the like is well known to Modern developments in the design of internal comh n; bustion engines, with increasing engine Speeds and (10111- The alkenyl substituted acids or anhydrides of the type pression ratios, have imposed a severe strain on the lubridescribed above may he t jfi d by reaction with a w. cents p y In particular, the crankcase l is ra rated or unsaturated aliphatic alcohol, employing the to a high temperature and in the Course Of its eirelllatioh usual esterification methods, preferably with the aid of through the engine is p y exposed to under cohdian esterification catalyst such as p-toluene sulfonic acid t{.0118 highly conducive to destructive OXidatifmt and a water entraining agent. Typical examples of suittive breakdown of the oil results in the formation of acidic 25 able alcohols which may be employed are the f ll i products which corrode bearing surfaces and do considerable harm to the engine generally. Furthermore, the Methyl alcohol metallic corrosion products have the effect of catalyzing Ethyl alcohol further oxidative breakdown of the oil. Allyl alcohol It is also known that in modern internal combustion n-Propyl alcohol engines, such as aviation gasoline engines operating at n-Butyl alcohol relatively high temperatures due to their high power Isobutyl alcohol output, or in high speed diesel engines due to incomplete n-Amyl alcohol combustion, piston rings have a tendency to become stuck Isoamyl alcohol in grooves. Lacquer and carbon formation appear to be Allyldiethylcarbinol the principal reasons for this occurrence. Moreover, n-Octyl alcohol scufiing of top lands due to the formation of hard carbon, Z-ethylhexyl alcohol particularly when using high viscosity index oils, may Cetyl alcohol cause serious damage to the engine. 7 Oleyl alcohol It has been found, in accordance with the present in- Isodecy10 0 alcohol vention, that destructive oxidation of lubricating oils and 150 trideeyl alcohol deposition of carbon and lacquer may both be substan- Iso hexadecyl 0x0 alcohol. tially reduced by the addition to the oil of a small amount of a new additive. This additive may be described as a P of alcohols especially adapted for use in 011- reaction product obtained by reacting a sulfide of phosnectlon wtth the present invention are the so-called 0x0 phorus or other combinations of the elements sulfur and alcohols- These alcohols are P p y the eaCtiOIl f phosphorus with an aliphatic alcohol ester of an alkenyl carbon monexlde and hydrogen With fins o tainable succinic acid containing a single alkenyl group of 4 to from petfoleum Products follewed y hydrogenation of 24 carbon atoms Th ester may b a di a h lf ester, the resulting aldehydes. Materials such as di-isobutylene or a group I or II metal salt of a partial e te M l and C7 olefins are suitable for this purpose; also higher salts of the h h lf i d reaction products, whenl molecular weight olefinic materials are sometimes emthe metal is Selected f m metals f group I or H f ployed. The alcohols obtained in this manner are prithe periodic table, may also be employed to advantage, mary alcohols and normally have a highly branched chain especially when the detergent efiects of the additive are structure y y mcnohydric aliphatic alto be emphasized. These additives have the effect of rewhole havlng h f of 1 to 30 Carbon atoms P ducing oxidation and the f ti f carbon deposits molecule and containing no more than one olefinic double of sludge in lubricating oils They are also Sometimes bond are used. Particularly preferred alcohols are those useful, when added to lubricants, for protecting metallic having 6 to 20 e e 'f surfaces of such engines against corrosion. The additives The alkenyl Succmlc aeld anhydtide y he Partially are l f l gemrahy as anthoxidants i mineral oil or completely esterified with one or more alcohols of the products f all types above mentioned type. The half ester may be converted The alkenyl succinic acid used to form the esters may into a metal Salt by reaction With a hydroxide, Carbonate be conveniently prepared by condensing mono-olefins with of other basic reacting compound of a metal of group I l i a id or maleie a hydrid employing a elevated or II of the periodic table. Such metals include sodium, temperature, for example C. or higher. The conpotassium, calcium, strontium, barium, etc. although densation process results in the formation of an alkenyl substituted succinic acid or anhydride. A typical reaction follows:

barium salts are particularly preferred. This reaction may be conducted at a temperature in the range of about 50 to 400 F.

3 Specifically, the esters to be reacted with the reactive sulfurphosphoruscontaining material have the following formula:

L angry wherein R is an alkenyl radical having 4 to 24 carbon atoms, R is selectedfrom the group Consisting of alkyl and alkenyi radicals having 1 to 30 carbon atoms, M is selected from the group consisting of R, group 1 andll metals and hydrogen, and It is l to 2. The integer it will be 2 when a divalent metal salt is prepared.

The esters or ester salts derived from the alcohols and alkenyl succinic acids described above' are then reacted with a reactive sulfur and phosphorus-containing material. It is preferable to employ a sulfide of phosphorus, such as P253, P285, P483 or P437, or mixtures thereof. Mixtures of elemental sulfur and elementalphosphorus may likewise be employed, in which case it is preferable to employ powered sulfur and, white phosphorus. Likewise, a mixture of one or more sulfides of phosphorus and elemental sulfur and/or elemental phosphorus may be employed. The amounts of sulfur and phosphorus which are advantageously employed depend upon such factors as the number of double bonds present in the ester in double-bonded hydrocarbon groups, and the ultimate phosphorus and sulfur content desired in the product. For example, about 0.2 to 1.5 mols of a sulfide of phosphorus may be used for each mol of ester or ester salt. It is generally preferred to react from 0.1 to 1 atom of phosphorus and 0.1 to 3 atoms of sulfur for each .such double-bond in the ester molecule. of sulfide of phosphorus, such as P255, is preferably used for each mol of double bond. in general, the temperature at which the reaction of the sulfide of phosphorus or mixture of sulfur and phosphorus with the ester is carried out is in the range of about 200 to 500 F., preferably about 2S0400 F., and the time required to substantially complete the reaction is generally from 1 to hours. Usually, at least about 0.3 to 0.5 weight percent of both sulfur and phosphorus should be introduced into the product.

It is generally desirable to employ an organic solvent during the reaction. The solvent'should be relatively inert to phosphorus and sulfur. Such solvents include, for example, benzene, o-dichlor-benze ne,"lubricating oil base stocks, and the like. In preparing an additive for use in a mineral oil, it is usually convenient to employ a mineral oil as the medium for the reaction, and thus prepare a concentrate for convenient use in blending with the oil.

As stated above, the phospho-sulfurized reaction products prepared as described may be used as such or in the form of their group I or II metal salts. The metals employed are preferably group II metals and the barium salts are particularly desirable and convenient to prepare. Such metal salts may be prepared by reacting the phosphorus and sulfur-containing reaction product with metallic oxides or hydroxides or other basic reacting compounds of such metals. The metallic compounds may be added to the reaction mixture in which the phosphorus and sulfur-containing reaction products are formed, and the mixture heated to a temperature of the range of 50400 F. Sufiicient basic reacting metallic compound may be used to neutralize the phospho-sulfurized ester.

The additives of the present invention are preferably added to mineral oils in proportions ranging from 0.01% to the proportion being preferably about 1.0 to 5.0% when employed as corrosion inhibitors and detergents in mineral lubricating oils. The proportions giv- About one-half mol ing the best results will vary somewhat according to the nature of the additive and the specific quality characteristics of the oil. to be. improved by the use of the additive. For commercial purposes, when the additives are to be employed in mineral lubricating oils, it is convenient to prepare concentrated oil solutions in which the amount of additive in the compositions ranges from about 20 to 50% by weight, and to transport and store them in such form. In preparing lubricating oil compositions for use as crankcase lubricants, the additive concentrate is merely blended with the base oil in the required amount.

Below are given detailed descriptions of preparations of several examples of mineral oil additives of the type described above as well as various laboratory tests which were applied to determine their effectiveness when employed in lubricatingoil compositions. It is to be understood that these examples are given to illustrate the present invention and are not to be construed as limiting the scope thereof in any way.

Example 1 Product A.-The Lorol B half ester of Cur-C12 alkenyl succinic acid having a neutralization number of l 16 was prepared by partially esterifying C1o-C12 alkenyl succine' acid with Lorol B alcohol (a mixture of Clio-Cm alcohols having an average molecular weight of 207). 250 grams of the half ester were placed in a l-liter flask andneutralized with a solution containing 82 g. barium hydroxide and g. H2O. The water was removed by heating. A 20% concentration of the resulting barium salt of the half ester in a lubricant having an S. S. U. viscosity at 210 F. of about 50 was then prepared. The concentrate (Product A) had a neutralization number (mg. KOH per gram of product) of 6.6.

Product B.500 g. of Product A (containing about 0.1 mol of the barium salt of the half ester) was heated to 250 F. and 11.1 g. (about 0.05 mol) of P 5 were slowly added over a period of one hour with rapid stirring. The temperature was then raised to 300 F. and kept at that temperature for two hours. The. reddish brown product was then filtered through Hy-flo diatomaceous filter acid and analyzed:

Weight Percent Ash 3.88

Barium 2.26

Phosphorus 0.60 Sulfur 1.19 NeutralizationNo 9.49

Example 2.-Carb0n black dispersion test This test is used to measure the dispersive power of the lubricating oils. 500 cc. of a 1% blend of Product B in a solvent-extracted Mid- Continent praflinic base oil of 52 seconds viscosity (Saybolt) at 210 F. was agitated with 6% by weight of carbon black and allowed to settle for24 hours at a temperature of 200 F. For comparisona similar amount of base oil was similarly treated.

-It is seen that the metalsalt ofthe half ester imparted dispersive properties to the oil containing it.

greases h oil and 1.0% of Product B. The results are shown in Table II:

TABLE II Varnish rg t e Base oil 3.0 Base Oil+1.0% Product B 0.5

tergency characteristics of the oil containing it. 25

Example 4.-Lab0rat0ry bearing corrosion test A blend was made containing 1% of Product B in a lubricating oil base consisting of a well refined, solvent extracted parafiinic mineral lubricating oil of S. A. E. viscosity grade. This blend and a sample of the unblended base oil were submitted to a corrosion test designed to test the effectiveness of the additive in inhibiting corrosion of a typical copper-lead bearing.

In this test 500 cc. of the oil were placed in a glass oxidation tube (13 inches long and 2% inches in diameter) fitted at the bottom with a /1 inch air inlet tube perforated to facilitate air distribution. The oxidation tube was then immersed in a heating bath so that the oil temperature was maintained at 325 F. during the test. Two quarter sections of automotive bearings of copperlead alloy of known weight having a total area of mg. in weight, determined by interpolation of the data.

obtained in the various periods.

TABLE III Bearing on Tested (Houis) Base Oil... 13 Base Oil plus 1.0 Wt. Percent Product B 37 The oil containing Product B showed a much greater resistance to corrosion of the metal than the uncompounded base oil.

Example 5 A series of preparations were carried out in which Cur-C12 alkenyl succinic acid and Cs1o alkenyl succinic acid were esterified with various saturated and unsaturated aliphatic alcohols. The resulting esters were then directly phosphosulfurized with phosphorus pentasulfide.

Product C was prepared in the following manner. A l-liter, 4-neck flask equipped with a stirrer, thermometer, nitrogen inlet tube and gas exit tube was charged with 100 g. of the C13 Oxo ester of CID-C12 alkenyl succinic acid and 176.5 g. of a phenol extracted Mid-Continent distillate of 45.1 seconds (Saybolt) viscosity at 210 F. After heating the mixture to 250 F., 17.5 g. of P285 was added during 5 minutes and heating was continued to 300 F, at which temperature it was maintained for 4 hours. A slow stream of nitrogen was passed thru the mixture throughout the course of the reaction. The product was filtered while hot with Hy-flo leaving 15 g. of resinous material on the flask. Oil concentrate (Product C) contained about 40% active ingredient.

Products D through G were prepared substantially in accordance with the procedure employed in making Product C. Table IV, below, presents information on the properties of the esters, the molar ratio of ester to P285 used in the phosphosulfurization reaction and the analysis of the resulting products. In each case, the product contained about 40% by weight of active ingredient in oil.

TABLE IV Properties of Analyses of Product, Ester Molar Weight Percent Product Ester Treated gggg;

i??? gig P235 Phosphorus Sulfur o C13OXO6S1ZGI of 010-012 alkenyl 3.4 203 7 2 1 0. 5a 3. 71

succinic acid. 1) Gm Oxo" ester of 010-012 alkenyl 3.4 112 2/1 0.50 3.60

succinic acid. E Lorol B ester of C1fl O12 alkenyl 5.6 181 2/1 0.38 3.37

succinic acid. F Oleyl ester of Clo-C12 alkeny] 1.1 112 2/1 1.34 3.27

succinic acid. G n-decyl ester of CsC10 alkenyl 1.1 203 2.7/1 0.51 3.75

' succinic acid.

1 Neutralization number, mg. KOH/g. ester. 2 Saponification number, mg. KOH/g. ester.

square centimeters were attached to opposite sides of a stainless steel rod which was then immersed in the test oil and rotated at 600 R. P. M., thus providing sufficient agitation of the sample during the test. Air was then blown through the oil at a rate of 2 cubic feet per hour. At the end of each 4-hour period the bearings were removed, washed with naphtha, and weighed to determine the amount of loss by corrosion. The bearings were then repolished (to increase the severity of the test), reweighed, and then subjected to the test for additional 4- hour periods in like manner. The results are given in Table III, below, as corrosion life, which indicates the number of hours required for the hearings to lose 100 75 The above products were tested by the copper corrosion test which is a modification of the C. R. C. method, L l6445. Blends were prepared containing 0.5% by Weight of each of the active ingredients (Products B-G) in a solvent extracted Mid-Continent base oil having 48.3 seconds (Saybolt) viscosity at 210 F. A polished metallic copper strip was immersed in each blend and in a sample of the base oil for a period of one-half and three hours at 210 F. The extent of staining on each strip was then rated on a scale of from 1 (no stain) to 10 (black surface film). The results of these tests are given in Table V, below:

The phospho-sulfurized esters reduced the corrosiveness of the oil containing them. The phospho-sulfurized metal salt of the ester (Product B) had substantially no efiect.

The above products were also evaluated by the laboratory corrosion test described in Example 4. In this case, the blends testedwere prepared by dissolving 0.5% by weight of the active ingredient of each of the products in a white oil having a viscosity at 210 F. of 54.2 seconds (Saybolt). The white oil was a relatively unstable product obtained by successive treatment of a solvent extracted coastal lubricant base stock with sulfuric acidto remove colored bodies, aromatics and the like. A blend containing Product B in' this oil was also tested. The bearing corrosion life of the base oil per se and of each of the blends is given in Table Vi, below:

All of the products improved the ability of the base oil to resist corrosion. The Pass-treated C16 x0 ester of Clo-C12 alkenyl succinic acid was particularly eifective.

The products of the present invention may be employed not only in ordinary hydrocarbon. lubricating oils but also in the heavy duty type of lubricating oils which have been compounded with such detergent type additives as metal soaps, metal petroleum sulfonates, metal phenates, metal alcoholates, metal alkyl phenol sulfides, metal organo phosphates, phosphites, thiophosphates and thiophosphites, guanidine salts, metal xanthates and thioxanthates, metal thiocarbamates, and the like. Other types of additives, such as phenols and phe nol sulfides, may also be present.

The lubricating oil base stocks used in the compositions of this invention may be straight mineral lubricating oils or distillates derived from parafiinic, naphthenic, asphaltic or mixed base crudes, or, if desired, various blended oils may be employed as well as residuals, particularly those from which asphaltic constituents have been carefully removed. Hydrogenated oils or white oils may be employed. Synthetic oils such as the polyether and polyester types or those prepared, for example, by the polymerization of olefins or by the reaction of oxides of carbon with hydrogen or by the hydrogenation of coal or itsproducts may be usedv as such or in combination with each other and/or with mineral base lubricants. In certain instances cracking coil tar fractions and coaltar or shale oil distillates may also be used.

The additives are normally sufliciently soluble in the lubricant base stock, but in some cases auxiliary solvent agents may be used. The lubricating oils will usually range from about 40 to 150 seconds (Saybolt) viscosity at 210 F. The viscosity index may range from 0 to or even higher.

Other agents than those which have been mentioned may be present in the oil composition, such as dyes, pour point depressants, heat thickened fatty oils, sulfurized fatty oils, sludge dispersers, anti-oxidants, thickeners, viscosity index improvers, oiliness agents, resins, rubber, olefin polymers, and the like.

What is claimed is:

1. As a new composition of matter a reaction product selected from the class consisting of: (A) the reaction products obtained by reacting, at a temperature in the range of about 200 to about 500 F. a reactive sulfur and phosphorus-containing material with an ester of an alkenyl succinic acid of the formula in whiclrR is an alkenyl radical having 4 to 24 carbon atoms, R is selected from the group consisting of alkyl and alkenyl radicals having in the range of 1 to 30 carbon atoms, M is selected from the group consisting of R, a group I and II metal, and hydrogen and n is 1 to 2, and (B) metal salts of said reaction products and a group I and group II metal.

2. A composition as in claim 1 wherein said sulfur and phosphorus-containing material is a sulfide of phosphorus.

3. A composition as in claim 2 in which in the range of 0.2 to 1.5 mols of said sulfide of phosphorus per mol of said ester are reacted at a temperature in the range of about 250 to 450 F. for 1 to 10 hours.

4. A composition as in claim 3 wherein M is barium.

5. The process for producing a phosphorus and sulfur containing material which includes the steps of reacting together a compound selected from the group consisting of the esters of C4 to C24 alkenyl succinic acids and C1 to C30 aliphatic alcohols and the group I and group II metal salts of the partial esters of said succinic acids, and a sulfide of phosphorus at a temperature in the range of about 200 to 500 F.

6. A process as in claim 5 wherein said sulfide of phosphorus is phosphorus pentasulfide.

7. A process as in claim 6 wherein said reaction is carried out in the presence of an organic solvent.

8. A composition as in claim 1 wherein said R group has in the range of 6 to 20 carbon atoms.

9. A composition as in claim 8 wherein said R group has in the range of 6 to 16 carbon atoms.

10. As a new composition of matter, the product of the process of claim 5.

11. A process as in claim 5 in which said phosphorus and sulfur-containing material is further reacted with a metallic basic reacting compound, in which the metal is selected from groups I and II of the periodic table, to

' form a metal derivative thereof.

12. The process which comprises the steps of reacting the barium salt of an ester of aliphatic alcohol having 6 to 20 carbon atoms and a CG-CI6 alkenyl succinic acid with phosphorus pentasulfide at a temperature in the range of about 250 to 400 F.

13. A process as in claim 12 wherein said alkenyl succinic acid is a C1oC12 alkenyl succinic acid.

14. The process which comprises the steps of reacting together an esterof an aliphatic alcohol having 6 to 20 carbon atoms, and a Cs-Cie alkenyl succinic acid with 9 phosphorus pentasulfide at a temperature in the range of about 250 to 400 F.

15. As a new composition of matter, the product of the process of claim 12.

16. As a new composition of matter, the product of the 5 process of claim 14.

References Cited in the file of this patent UNITED STATES PATENTS Hersh July 25, 1950 

1. AS A NEW COMPOSITION OF MATTER A REACTION PRODUCT SELECTED FROM THE CLASS CONSISTING OF: (A) THE REACTION PRODUCTS OBTAINED BY REACTING, AT A TEMPERATURE IN THE RANGE OF ABOUT 200* TO ABOUT 500* F. A REACTIVE SULFUR AND PHOSPHORUS-CONTAINING MATERIAL WITH AN ESTER OF AN ALKENYL SUCCINIC ACID OF THE FORMULA 